A gear-changing device where the gear-changing elements (for ex., dog rings) of the toothed gear system are moved to their switching position via a slider-crank mechanism is shown and described in the applicant's prior patent application (German patent application P 41 37 145.3 filed on Nov. 12, 1991 or European patent application). The slider-crank mechanisms are here formed by oscillating cranks and a slide rod. The oscillating cranks are connected with the slide rod, via coupling mechanisms, according to the speed to be engaged or there is produced a stationary stop, of the oscillating crank, on a part that is formed in the housing.